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Charley Shows Progress, Pitfalls in Forecasting
Mon Aug 16, 7:06 PM ET

MIAMI (Reuters) - A few decades ago, the earliest warning Floridians
would have had of a hurricane would have been black clouds on the
horizon. Now people are complaining after Hurricane Charley hit shore
at a point just 60 miles off from the track projected by
meteorologists.

Hurricane predictions have come a long way since the first
earth-mapping satellite was launched and, more significantly, since
elaborate computer modeling became possible.

Despite the surprise expressed by some when Charley roared ashore on
Friday farther down the southwest Florida coast than expected, and far
stronger than expected, forecasters said the National Hurricane Center
(news - web sites) could not have done a better job.

"They did a fabulous show actually," said Eric Williford, a
meteorologist with private Raleigh, N.C.-based forecasters Weather
Predict Inc. "Their track error was very low. They outperformed most
of the numerical models."

The National Hurricane Center in Miami issued storm warnings for the
entire western coast of Florida as Charley stormed across Cuba, grazed
the Florida Keys and then appeared likely to make a northeastward
swing toward land.

Its predictions for the storm's track indicated that the populous
metropolitan area of Tampa-St. Petersburg was the hurricane's most
likely target but warned that the slightest change in direction would
make a big difference on a slanting coastline like southwestern
Florida's.

In the end, Charley came ashore at Port Jackson and Punta Gorda, 60
miles south of Tampa. It also grew suddenly into a deadly Category 4
storm -- the second-most powerful on the five-category Saffir-Simpson
scale -- while the hurricane center had at most predicted Category 3
winds.

Some residents who remained in flimsy mobile homes and officials who
initially feared many more had died than the 17 confirmed by Monday
criticized what they saw as the vagueness of warnings about the threat
to Port Jackson and Punta Gorda.

CRITICISM IRRITATES

The criticism, which meteorologists say is unjustified, has irritated
some staff at the hurricane center.

"I've been around for a long time so I'm not so much frustrated by
this stuff because I'm used to it," said hurricane center
meteorologist Miles Lawrence.

But Lawrence said the fact that forecasters did not predict Charley
would become a Category 4 hurricane should not have made a difference
for people in the warning area because guidelines called for them to
evacuate anyway and for trailers to be evacuated in a Category 1
hurricane.

Vast improvements have been made in recent years in predicting a
hurricane's likely path through computer modeling, although an error
margin amounting to a 75-mile diversion over 24 hours is built in.

The real problems arise when it comes to forecasting a storm's
intensity, which can be influenced by a host of factors, some of them
still unknown.

Weather forecasters who work for the insurance industry to predict how
much damage a storm may cause are also focused on another quality --
the size of a hurricane's destructive core.

For Charley this was an extremely small 6 miles, compared with a more
usual 25 miles, said meteorologist Kyle Beatty of California-based
Risk Management Solutions.

The result was a 10-mile-wide swath of destruction more commonly
associated with tornadoes than with hurricanes. But it also meant
damage to insured properties was a relatively mild $5 billion or so.